Traditionally, there have been proposed magnetic recording media of multiple layer structure comprising an upper layer containing a magnetic powder and a lower layer containing a nonmagnetic powder e.g., Japanese Patent Publication Open to Public Inspection (hereinafter referred to as Japanese Patent O.P.I. Publication) Nos. 418/1988 and 191315/1988), aiming at improvement of electromagnetic converting property in the magnetic recording medium.
However, these magnetic recording media are not intended to be applied to digital recording media. Because the upper layer is relatively thick, there is a problem of difficulty in offering a satisfactory electromagnetic converting property and running durability for digital recording media due to a significant loss of layer thickness and spontaneous loss of magnetism, despite the double-layer structure.
Also, in magnetic recording media such as a video tape, because recorded signal depth varies among signals, preference has been given to magnetic recording media of multiple-layer structure comprising magnetic layers containing different magnetic powders suitable to respective signals. However, in producing such a magnetic recording medium of multiple-layer structure, which is normally achieved by multiple-layer coating methods such as the wet-on-wet coating method, there is a problem of electromagnetic converting property deterioration upon tape regeneration because of magnetic layer surface roughness upon coating and drying in some cases according to layer material composition and paint viscosity, etc.